Cutting and tunneling machines in the mining field utilize power-driven continuous chains or large diameter power-driven wheels which carry circumferentially spaced cutting bits having wear points projecting from the wheel to dig into and abrade the material to be removed from the mining area. In some areas, it has been the practice to supply a coolant to an area near each cutting point to lower the temperature of the bit and thus improve its life and also to wash the dust and fines away from the bit.
Examples of devices which furnish coolant in this manner are found in the following U.S. patents:
______________________________________ Barnstorf 4,333,687 June 8, 1982 Clemmow 4,453,775 June 12, 1984 Bergqvist 4,488,759 Dec. 18, 1984 Zitz et al 4,506,932 Mar. 26, 1985 ______________________________________
The present invention has as an object the provision of a coolant system in combination with a wear sleeve which allows the cutting bit to rotate and thus even the wear, and also reduces the wear on the mounting block secured to the rotating wheel.
A further object is a simplified and thus lower cost system for applying coolant which is also more rugged for the extreme wear conditions which pertain in the mining field.
A further object is the provision of a structure which permits a quick change of the bit and sleeve in the block and the substitution, when desired, of a sleeve with a modified nozzle when conditions call for such a substitution to vary the water spray.
A still further object is the provision of a coolant sleeve and bit mounting which provides increased service life of the three elements, namely, the bit, the sleeve and the mounting block.
Other objects and features of the invention will be apparent in the following description, accompanying drawings, and claims in which the invention is described together with details to enable persons skilled in the art to practice the invention, all in connection with the best mode presently contemplated for the invention.